Bear StearnsLondon Healthcare Conference

16 March 2004

Matthew Emmens Chief Executive Officer

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THE “SAFE HARBOR” STATEMENT UNDER THE PRIVATE SECURITIES LITIGATION REFORM ACT OF 1995

Statements included herein that are not historical facts, are forward-looking statements. Such forward-looking statements involve a number of risks and uncertainties and are subject to change at any time. In the event such risks or uncertainties materialize, Shire’s results could be materially affected. The risks and uncertainties include, but are not limited to, risks associated with the inherent uncertainty of pharmaceutical research, product development and commercialization, patents, government regulation and approval, including but not limited to the expected product approval date of lanthanum carbonate (FOSRENOL®), the impact of competitive products, including but not limited to the impact of same on Shire’s ADHD franchise, the implementation of the planned reorganisation and other risks and uncertainties detailed from time to time in our filings, including the Annual Report filed on Form 10-K by Shire with the Securities and Exchange Commission.

Trademark Information:Unless otherwise indicated, certain product names set out in this document are trademarks of the Shire Group, many of which are the subject of trademark registrations in certain territories. These names include, but are not limited to, Adderall, Adderall XR, Agrylin, Colazide, Carbatrol, DextroStat, Fluviral S/F, Fosrenol, Pacis, Pentasa, ProAmatine, Solaraze, Troxatyl, EnSoTrol, Microtrol, OptiScreen, ProScreen, Solutrol, and Xagrid. 3TC, Epivir, Combivir, Trizivir, and Zeffixare trademarks of GlaxoSmithKline. Reminyl and Concerta are trademarks of Johnson & Johnson. Aricept is a trademark of Pfizer / Eisai. Exelon is a trademark of Novartis. NeisVac-C is a trademark of Baxter International. Adept is a trademark of ML Laboratories. MethyPatch is a trademark of Noven Pharmaceuticals.

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Agenda

Full Year 2003 – Strategy update

Financial Review

R&D Review

Conclusion

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Another excellent year for ShireContinued success of Adderall XR®Pipeline progress

6 products in Registration 2 projects in Phase III2 in Phase II* Potential for 11** launches in the 2004-2007 period

Fosrenol®EU – initiated labelling discussions with Reference Member StateUS – approvable letter responses delivered to the FDA

NDA for Bipotrol® filed; the first US carbamazepine treatment for bipolar disorder

Highlights

*excluding SPD754 and Troxatyl**excluding SPD754 and Troxatyl but including SPD465 in Phase I

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Strategy

Search, Develop and Market – not inventM&A / in-licensing focused on US marketSeek to acquire products with broader IP platformsImplementation

early stage therapeutic research exit completed Q3 2003exit vaccines around mid 2004new management and infrastructure organisation to deliver strategy

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Rationale:Reduce complexityEliminate inefficiencyCreate a new world class center in USBuild effective organisation Platform for managing future growth

Implementation:Reduce US number of sitesNew management processesRelocate and hire talentOne US office in world Pharmaceutical heartland

New organisation to deliver strategy

approx $55 million restructuring cost

to create an efficient, streamlined

with long term infrastructure savings

as business grows

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New organisation to deliver strategy

Therapeutic area

focus

Commercial and R&D alignment

Structure and sites

in N America (14 to 4)

Platform for growthPlatform for growth

Global team building and communication

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Financial Highlights

162.6c48.9c- ADS

+17

+22+22

+14%

+10

+21+17

+19%

54.2c

276.1

394.6384.5

1,237.1FY 03Q4 03

EPS (diluted):16.3c- Ordinary shares

82.9Net Income

122.4114.5

Operating incomeIncome before taxes

344.2Revenues

Millions of USD, except per share amounts

+18 +11

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-1+1487.299.3Pentasa

-3

+16

+11

+49

Growth (%)

+250.949.3ProAmatine

+545.352.4Carbatrol

+7119.2132.5Agrylin

+49317.9474.5Adderall XR

US Rx Growth (%)*

FY 2002FY 2003

Millions of USD

Major Product Sales – FY 2003

* Source: IMS Data

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* Foreign exchange movements have contributed 4% to reported growth** Foreign exchange movements have contributed 6% to reported growth*** Includes Reminyl

203.6 34.3

24.7

144.6

FY 03 Royalties

+16+63

+17**

+9*

Growth (%)FY 03/FY 02

8.221.1Other ***

FY 01 Royalties

FY 02 Royalties

145.2174.8Total

16.921.2Zeffix

120.1132.53TC

Millions of USD

Royalty Income – FY 2003

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32

3717

8416

FY 03

333632Operating margin

2817

8317

Q4 03

3317

8119

Q4 02FY 02

18R&D : Revenues39S,G&A (excl. D&A) :

Product sales

84Gross margin16COGS : Product sales

Financial Ratios

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Cash Flow – FY 2003Millions of USD

Net cash surplus for FY 2003 : $230 million

Cash generation + $480

Tax / interest- $100

Products / equity investments- $52

Fixed assets - $51

- $47 Financing

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* Cash, cash equivalents, and marketable securities

1,414

1,036

1,923

31.12.03

1,275

896

1,783

30.09.03

1,214Gross cash*

806Net cash

1,573Net assets

31.12.02

Balance SheetMillions of USD

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Potential Uses of Cash

Introduction of dividend policy First interim payment in 2004:

1 pence per share for the six months ending June 2004

In-licensing and M&A Opportunities Remains primary use of cash

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Outlook

Revenue growth for 2004: high single digit range*Earnings for 2004

Subject to:Internal re-organisation – restructuring costs (approx 23 cents per ADS)Outcome of planned exit of the vaccines business

Beyond 2004EPS growth on average in mid teens rangeAim to maintain consistent margins

* Despite loss of exclusivity on PROAMATINE in Q3 2003 and AGRYLIN in the US in Q4 2004

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R&D Content

R&D portfolio summary

Registration Update: Featuring Bipotrol, first UScarbamazepine bipolar treatment

Emerging Data: Featuring SPD503; a novel non-stimulant for the treatment of ADHD

Summary / Pipeline flow

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Progress with R&D Portfolio

In Phase IIISPD476

labelling discussions

Fosrenol EU

filedAgrylin paed exclusivity

filedPentasa 500mg

responses filedFosrenol US

studies completedAdderall XR paed exclusivity

Adult responses filed

Adderall XR

filedBipotrol NDA

Pipeline Progression

In discussionSPD754 (HIV)

All development projectsVaccines exit

SPD760 (HCV)

Troxatyl

SPD756 (HIV)

Out-licensing

Agrylin – Japan

Fosrenol - Japan

Out-licensed

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Characteristic range of manic and/or depressive symptoms

Licensed treatments include: Lithium, Chlorpromazine, Valproate, Olanzapine, Lamotrigine, Risperidone, Quetiapine, Olanzapine/fluoxetine

Extensive off-label use of anti-convulsants and atypical anti-psychotics as monotherapy and/or combination use

Individuals respond to some drugs but not others and / or have troublesome side effects

Anti-epileptics are foundation therapies yet no carbamazepine products licensed in US for bipolar disorder

BIPOTROL: Patient Need

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BIPOTROL: Market Potential

Estimated disease prevalence of 3% to 6.5%*Diagnosis rate is accelerating because of increased recognitionCBZ classified as a 1st line mood stabilizer by APA guidelines

Bipotrol key features:

First carbamazepine indicated for bipolar disease in USUnique formulation with smooth coverageSpecific dose titrationFavourable side effect profile

New product introductions may prove complementary to Bipotrol

*Angst. J Affect Disord. 1998;50:143-151.

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BIPOTROL Study 3043-week, DB, PC, Parallel-Group Safety and Efficacy Study of bipolar I disorder (n=239)

27.9

20.8

-7.1

28.5

13.4

-15.1

-20

-15

-10

-5

0

5

10

15

20

25

30

Mean Total Score

Placebo BipotrolTreatment Group

Young Mania Rating Scale Total Score (ITT Population; Endpoint = LOCF at Day 21)

BASELINE (BS) ENDPOINT (EP) Change (EP - BS)

p value: compared to placebo following ANCOVA with bas eline s core as covariate

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BIPOTROL Study 304

3-week, DB, PC, Parallel-Group, Safety and Efficacy Study of bipolar I disorder (n=239)

14.2

33.3 ** 31.6

63.5 ***

43.4

79.8 ***

32.2

65.0 ***

0.0

20.0

40.0

60.0

80.0

100.0% Improved

DB Day 7 DB Day 14 DB Day 21 EndpointDB Treatment Week

% Patients Improved as Assessed by CGI-Improvement During DB Treatmentt(ITT Population; Endpoint = LOCF at Day 21)

Placebo Bipotrol

* p < 0.05 ** p < 0.01*** p <0.001 compared to placebo

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BIPOTROL: Current status

New data (study 304) reinforces efficacy seen in previous work

Favourable side effect profile (weight gain / cosmetic)

NDA filed February 2004

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SPD503: Profile

Guanfacine originally used off-label in refractory ADHD patients or in those with contraindications to stimulants

Non-scheduled, non-stimulant compound

Established safety profile for active ingredient in adults

On approval, will be the first guanfacine product licensed for ADHD

Novel, patent protected, once-daily formulation of guanfacine

Shire holds license to use-patent in ADHD

Paediatric phase III started February 2003

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38.14

28.97

-8.84

35.93

20.88

-16.01

36.77

20.98

-16.44

38.40

19.21

-19.13-20.00

-10.00

0.00

10.00

20.00

30.00

40.00

Mean Total Score

Placebo 2 mg 3 mg 4 mgTreatment Group

ADHD Rating Scale: Mean Total Score at Endpoint and Change in LS Mean from Baseline (ITT Population)

BASELINE ENDPOINT Change in LS Mean

SPD503: Study 301

8-week, DB, PC, Parallel-Group Safety and Efficacy Study (n=345)

** p<0.001; *** p<0.0001 (adjusted Dunnett test compared to plecabofollowing ANCOVA with baseline score as covariate

*******

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Study 301 demonstrated highly statistically significant differences from placebo for all dose groups using ADHD-RS, Conners Parent and Teacher Rating Scales, Parent Global Assessment and CGI

Safety profile consistent with established profile for guanfacine(somnolence, sedations, fatigue) with potential for improvement of incidence, particularly dry mouth

Target filing date 2005

Patent protection through 2015

SPD503: Status

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Key Projects Flow

RegP3P2P1

FOSRENOL

XAGRID (EU)

METHYPATCH (ADHD)

ADDERALL XR (adult)

SPD503 (ADHD)

SPD480 (UC) 2006

SPD465 (ADHD) H1 2004 2005

SPD473 (ADHD) 2006

BIPOTROL (Bipolar) Feb 2004

Pentasa 500mg (UC) Mar 2004

SPD476 (UC) 2005

H2 2004

Sep 2003

2005

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Conclusion

Another excellent year for ShireStrategy implementation well underway

Restructured and refocused Global team building and efficient communicationPlatform for future growth

Gearing up late stage pipelineExciting data for Bipotrol and SPD503Fosrenol progress11 potential launches by 2007

Active in-licensing / M&A Dividend policyConfident outlook for 2004 and beyond